Magnetic field effects on spin relaxation in heterostructures

Effect of a magnetic field on electron spin relaxation in quantum wells is studied theoretically. We have shown that Larmor effect and the cyclotron motion of the carriers can either jointly suppress D'yakonov-Perel' spin relaxation or compensate each other. The spin relaxation rates tensor is derived for any given direction of the external field and arbitrary ratio of bulk and structural contributions to the spin splitting. Our results are applied to the experiments on electron spin resonance in SiGe heterostructures, and enable us to extract spin splitting value for such quantum wells.